(-)-.DELTA..sup.9 -Tetrahydrocannabinol, one of the physiologically active components of cannabis, has recently encountered a renewed interest in the art, especially in view of the possibility of its therapeutical applications. Many of the processes for its preparation make use of (+)-p-mentha-2,8-dien-1-ol as an intermediate [J. Amer. Chem. Soc. 96, 5860 (1974); U.S. Pat. No. 4,025,516 and Helv. Chim. Acta 52, 1102 (1969) for example] which can be prepared from limonene via its oxidation with singlet oxygen or via an enzymatic reaction [see Ann. Chem. 674, 93 (1964) and Chem. Abstr. 85, 19027 (1976), respectively].
The present invention has the advantage to provide a new and original synthetic process for the preparation of (+)-p-mentha-2,8-dien-1-ol in a small number of reaction steps by making use of cheap and easily available reactants, thus rendering the whole synthesis commercially more attractive.